What PAR do you like for Derasa Clams?

Tft12 · Jul 4, 2018

What PAR range seems best for Derasa Clams?

Jeff Hall · Jul 4, 2018

From my understanding maxima's are light hogs while Derasa's can be kept in lower light.

DSC reef · Jul 4, 2018

I wouldn't go any less than 200 par.

cooltowncorals · Jul 4, 2018

Search Dana riddle coral par levels he has a chart I think they can go 900+ if they are under 2 inches you need to feed them if they are bigger than 2 inches light alone is enough. From my research the difference between them getting 200 and 900 par is just growth rate should be healthy either way.

DSC reef · Jul 4, 2018

I don't believe clams need to be fed no matter the size. It won't hurt to dose live phyto here and there but direct feeding is not necessary. Also, par has a lot more to do with just growth rates. Keeping a maxima low in the tank at 200 par isn't just going to make it grow "slower", it will need a lot more par to thrive. @jda do you have any par recommendations? Plus, the quality of light also matters as well.

Tft12 · Jul 4, 2018

Thanks everyone. I'll find the chart. I have an ORA Derasa that's about 3.5 inches. Arrived looking great, still looks really good but I'm not sure if the middle MIGHT be bleaching very slightly. It's keeping itself open quite wide during the day (perhaps the pigment looks slightly lighter because it's keeping itself so wide/stretched open?). I always keep angels so I haven't had a clam in my system for about 15 years, at that time it was a Maxima under halides and it did great. Now it's a Derasa under LEDs. I know there are a lot more options for a clam not doing well besides improper light, I just wanted to explore this aspect since I couldn't find PAR recommendations for Derasa clams in the clam care stickies. I just remeasured and it's getting about 200-220 PAR.

CNDReef · Jul 4, 2018

I’ve heard you can throw whatever you want at clams for par and they’ll take it ( on the max side )
My squamosa is on the sand at 230 par

TheSchwenkster · Jul 4, 2018

Tft12 said:
Thanks everyone. I'll find the chart. I have an ORA Derasa that's about 3.5 inches. Arrived looking great, still looks really good but I'm not sure if the middle MIGHT be bleaching very slightly. It's keeping itself open quite wide during the day (perhaps the pigment looks slightly lighter because it's keeping itself so wide/stretched open?). I always keep angels so I haven't had a clam in my system for about 15 years, at that time it was a Maxima under halides and it did great. Now it's a Derasa under LEDs. I know there are a lot more options for a clam not doing well besides improper light, I just wanted to explore this aspect since I couldn't find PAR recommendations for Derasa clams in the clam care stickies. I just remeasured and it's getting about 200-220 PAR.

Sounds like on the right track. Might be worth a picture to help you diagnose.

Tft12 · Jul 4, 2018

This image is probably the most accurate. If I saw this clam at a store I wouldn’t think it’s bleached, but I think that perhaps the middle is a little lighter than it was a couple weeks ago. Since I’m new to Derasas any possible change draws my attention.

Retro Reefer · Jul 4, 2018

My derasa doesn’t like to much light so I keep my nanobox dialed back not sure of the par but when I push it up he quickly looks mad.. been in tank around 2 years was about 2” when I got it and about 5” now.. pics under whites top and blues bottom.. WILD GUESS mines at about 150 par

Tft12 · Jul 4, 2018

Thanks @Retro Reefer. Those are great images.

What tells you when the clam isn’t as happy? Not open as much?

Looks like all clams are a bit lighter in the middle tissue.

Retro Reefer · Jul 4, 2018

Tft12 said:
Thanks @Retro Reefer. Those are great images.

What tells you when the clam isn’t as happy? Not open as much?

.

It can be a combination of things including not opening much but generally when mine is mad the mantle doesn’t expand fully around the edges, the center may get puffy looking and the colors will be off..

jda · Jul 5, 2018

200-250 might work for a T. Deresa. They can still take more than you can give them - Dana Riddle has tried to find saturation points with T. clams, and was not really able to. Some are out of the water, or just a few inches below the water in full sunlight at 2300 PAR... some are deeper. They digest excess zoox since they have a stomach and stuff.

Clams are full of all kinds of false-positives. Being totally open all of the time can be a good, or bad thing. Full mantle extension can be a sign that the clam needs more light. Being out all the time also means nothing since clams can be out all of the time and then waste away in 2 days out of nowhere because they were starving the whole time. The only positive-positive is new shell growth. Outside of this, response to light and being open, but not stretched all the way open are mostly good signs.

As for PAR for maximas, you cannot likely grow them under 200 PAR... they don't just grow slower, they die of starvation. I won't get onto my full-out soap box about quality of lighting, but full daylight sources seem to raise the trickier clams better... not impossible with others, but just a lot harder.

Lasse · Jul 5, 2018

In July 2017 I got this two small deresa clams. They was around 2.4 " when they arrive to my home

180625 - one year later

The large one - around 5.3 " and the smaller - around 4.5 " all measurement on the shell

Another comparison - the one to the left is a newcomer and was about 2" when it arrive to my aquaria a month ago. The one to the right is my large one - was around 2.5" a year ago

The PAR level has all the time been below 200 - down to 80 - 90 PAR for the one in the corner. with my new light - PAR for the two near the middle - around 180 and the one in the corner around 110. The one in the corner get sunlight now and then. Never ever target feeding. Today I dose cyano bacteria (small pelagic ones) but have only done that for around 2 months. Now and then - it is rater much organic particles in the water.

I´m very satisfied with the growth and it has been a good growth in spite of low PAR

Sincerely Lasse

DSC reef · Jul 5, 2018

@Tft12 I'd suggest reading some articles by James Fatheree. I still would not suggest anything under 200 par and remember quality of light does matter. What might work for one person's mature tank might not work for you.

DSC reef · Jul 5, 2018

@Lasse those are some of the most colorful derasa I've seen, well done.

Lasse · Jul 5, 2018

DSC reef said:
@Lasse those are some of the most colorful derasa I've seen, well done.

When I got the first two - the one to the left was really red inside but with time it has been more blue white. I do not know if it is my fixture or not.

I have four Deresa

The smallest

The colour of this is funny If I look at it close it looks like this but if I stand 2 metres from the aquaria and look at it from another angle - the lines are more bluish! My wife notice this too!

This one I got the 12 of april and it was slightly larger than the smallest when I got it - it has grow a lot

The first two ar rather funny too. They have grow in two different styles - the largest is rather narrow but the smaller one is more compact and round. It has been below lower PAR but get sunlight for at least three hours during sunny days. Smaller one

Largest and the colours is little to much violet in this photo.

The growing edge of the three largest ones are around 1 - 2 mm as can be seen in this picture but the edge of the smallest on is around 5 mm.

You can see that they have to fight for their place and that sponges can attach to them

And algae grow on them

In addition to my low PAR readings I have to say that they are situated near the front window and they will get a lot of reflecting photons that my PAR meter do not measure

Sincerely Lasse

dwest · Jul 5, 2018

Lasse said:
When I got the first two - the one to the left was really red inside but with time it has been more blue white. I do not know if it is my fixture or not.

I have four Deresa

The smallest

The colour of this is funny If I look at it close it looks like this but if I stand 2 metres from the aquaria and look at it from another angle - the lines are more bluish! My wife notice this too!

This one I got the 12 of april and it was slightly larger than the smallest when I got it - it has grow a lot

The first two ar rather funny too. They have grow in two different styles - the largest is rather narrow but the smaller one is more compact and round. It has been below lower PAR but get sunlight for at least three hours during sunny days. Smaller one

Largest and the colours is little to much violet in this photo.

The growing edge of the three largest ones are around 1 - 2 mm as can be seen in this picture but the edge of the smallest on is around 5 mm.

You can see that they have to fight for their place and that sponges can attach to them And algae grow on them

In addition to my low PAR readings I have to say that they are situated near the front window and they will get a lot of reflecting photons that my PAR meter do not measure

Sincerely Lasse

Mine are doing well at about 100-140 PAR measured.

Dr. Reef · Jul 5, 2018

For desera clams a good quality of light about 6 to 8 hrs a day with PAR of 100-200 is sufficient to keep it alive and growing.

Shigshwa · Jul 7, 2018

I prefer to hit them with a good deal more than minimum at the very least, to be on the safe side. My sandbed clams get 250-300, my middle up clams get close to 500, happy as can be, just less mantle extension because high flow and light.